1. Field of the Invention
This invention relates to a reel of material in tape form.
2. Brief Description of the Prior Art
In automatic machines which use material in tape form, the tape to be fed to the machines is withdrawn from respective reels which when empty are automatically replaced by devices which grip the outer end of the new reel and join it to the inner end of an emptying reel.
In a new reel the outer end of the tape is generally kept fixed by a fixing element such as a gummed band or a piece of adhesive tape, which is applied partly to the outer end of the new tape and partly to the reel.
When changing the reel the outer end of the tape has to be released from the new reel, this being achieved by manually removing the fixing element or by automatically or manually cutting it at the outer end of the tape.
The outer end of the tape is then withdrawn from the new reel and is joined to the inner end of the tape from the empty reel by a connection element, or by welding if the tape is of thermoweldable material.
It often happens that the outer end of the new tape is joined to the inner end of the used tape in a station different from and following that in which the fixing element is removed.
The result of this is that in moving the reel between one station and the next the free end of the new tape frequently tends to again adhere to the reel. The reasons for this are numerous, for example the free end may tend to adhere to the reel because of the type of material with which the tape is formed, or because of the generation of magnetostatic phenomena.
The main reason causing and/or aggravating the problem is however the small tape thickness, which also makes it very difficult to separate the free end from the relative reel.
In this respect, the free end is withdrawn from the reel by using, for example, wedge-shaped members which because of the small thickness of the tape on which they have to operate are necessarily thin with sharp edges. The problem is aggravated by the fact that the wedge-shaped members have necessarily to be kept in contact with the reel, with the inevitable risk of cutting the tape.